Semiconductor device and its manufacturing method

ABSTRACT

A CF card ( 1 ) comprises: a casing constituted by two panel plates ( 2, 2 ) and a frame ( 3 ); and a printed wiring board ( 4 ) accommodated in the casing. A plurality of claw-like engaging parts ( 5 ) are provided to the peripheries of the panel plates ( 2 ). When the CF card ( 1 ) is assembled, the engaging parts ( 5 ) of the first panel plate ( 2 ) are inserted into through holes of a long groove ( 8 ) provided in the frame ( 3 ) and then the printed wiring board ( 4 ) is mounted on the panel plate ( 2 ) located at the inside of the frame ( 3 ). Thereafter, the engaging parts ( 5 ) of the second panel plate ( 2 ) are inserted into the through holes of the long groove ( 8 ) from the surface located in the opposite side of the frame ( 3 ). There are two types of engaging parts ( 5 ): one having lances and the other having holes. Inside the through holes, the lances of the engaging parts ( 5 ) of one panel plate ( 2 ) are inserted into the holes of the engaging parts ( 5 ) of the other panel plate ( 2 ).

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a semiconductor device and a method ofmanufacturing the same, and, more particularly, to a techniqueeffectively applied to a memory card.

BACKGROUND OF THE INVENTION

A memory card is a card-type semiconductor device mounting asemiconductor chip in which a memory LSI for data storage or programstorage is formed, and is connected to various kinds of electronicequipments such as a digital camera, a handheld PC, an audio recorderand the like when in use.

The memory card belonging to these kinds has a structure in which aprinted wiring board on which the above-mentioned semiconductor chip ismounted is accommodated in a casing (case). However, from a securitystandpoint, it is required that the casing has such a rigid structure asnot to be easily disassembled.

Meanwhile, in the case of a memory card for data storage in particular,the low cost thereof is required as one high priority. Therefore, thereduction in the manufacturing cost must be achieved by reducing thenumber of components of the casing to the utmost and by promoting theautomation of assembly thereof.

However, the conventional memory card has had problems of the fact thatequipment investment for the assembly thereof becomes expensive and themanufacturing cost is difficult to reduce in order to require a specialapparatus such as an ultrasonic welding machine or the like in theassembly thereof.

An object of the present invention is to provide a memory card havinghigh reliability by low manufacturing cost.

The above and other objects and novel characteristics of the presentinvention will be apparent from the description of this specificationand the accompanying drawings.

SUMMARY OF THE INVENTION

The typical ones of the inventions disclosed in the present applicationwill be briefly described as follows.

A semiconductor device according to the present invention comprises acasing constituted by a frame having a plurality of through holespenetrating through both surfaces thereof, a first panel plate attachedto one surface of said frame, and a second panel plate attached to theother surface of said frame, a printed wiring board on which asemiconductor chip is mounted being accommodated in said casing,

wherein a plurality of engaging parts each having a lance or a hole areformed on the peripheries of said first and second panel plates,respectively, and said engaging parts formed on said first panel plateand said engaging parts formed on said second panel plate are insertedinto said plurality of through holes formed in said frame, and saidlance provided in each of one plurality of engaging parts is insertedinto said hole provided in each of the other plurality of engagingparts.

A method of manufacturing a semiconductor device according to thepresent invention comprises the steps of:

(a) preparing a frame having a plurality of through holes penetratingthrough both surfaces thereof, and first and second panel plates inwhich a plurality of engaging parts each provided with a lance or a holein the peripheries thereof is respectively formed, and a printed wiringboard on which a semiconductor chip is mounted;

(b) pressing said engaging parts formed on said first panel plate intosaid through holes formed in said frame, thereby attaching said firstpanel plate to one surface of said frame;

(c) mounting said printed wiring board to said frame to which said firstpanel plate is attached; and

(d) after said step (c), pressing said engaging parts formed on saidsecond panel plate, into said through holes formed in said frame, andinserting said lance each provided in one of said engaging parts formedon said first panel plate and said engaging parts formed on said secondpanel plate, into said hole each provided in the others, therebyattaching said second panel plate to the other surface of said frame.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view showing the appearance of a semiconductordevice that is an embodiment of the present invention.

FIG. 1B is a perspective view showing the appearance of a semiconductordevice that is an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a semiconductor device that isan embodiment of the present invention.

FIG. 3 is a perspective view showing a panel plate of a semiconductordevice that is an embodiment of the present invention.

FIG. 4 is an enlarged view of an engaging part provided on a panel plateof a semiconductor device that is an embodiment of the presentinvention.

FIG. 5 is a perspective view showing a frame of a semiconductor devicethat is an embodiment of the present invention.

FIG. 6 is a plan view showing a frame of a semiconductor device that isan embodiment of the present invention.

FIG. 7 is a perspective view showing a printed wiring board of asemiconductor device that is an embodiment of the present invention.

FIG. 8 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 9 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 10 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 11 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 12 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 13 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 14 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 15 is a perspective view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 16 is a plan view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

FIG. 17A is a cross-sectional view illustrating a method ofmanufacturing a semiconductor device that is an embodiment of thepresent invention.

FIG. 17B is a cross-sectional view illustrating a method ofmanufacturing a semiconductor device that is an embodiment of thepresent invention.

FIG. 18 is a plan view illustrating a method of manufacturing asemiconductor device according to an embodiment of the presentinvention.

FIG. 19A is a cross-sectional view illustrating a method ofmanufacturing a semiconductor device that is an embodiment of thepresent invention.

FIG. 19B is a front view.

FIG. 20 is a plan view illustrating a method of manufacturing asemiconductor device that is an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following, embodiments of the present invention will be describedin detail with reference to the accompanying drawings. Components havingthe same function are denoted by the same reference symbols through allthe drawings for describing the embodiments, and the repetitivedescription thereof will be omitted.

A semiconductor device in this embodiment is a Compact Flash (registeredtrademark of SanDisk Corporation in U.S.A.) Card (hereinafter, referredto as a CF card simply), which meets CFA (Compact Flash Association)standards. FIGS. 1A and 1B are perspective views showing the appearanceof a CF card type I, wherein FIG. 1A is a view shown with a connector 9located in a front side and FIG. 1B is a view shown on the conditionthat a side opposite to the connector 9 is located in a front side. Inaddition, FIG. 2 is an exploded perspective view of the CF card.

As shown in the drawings, the components of the CF card 1 are: a casingconstituted by two panel plates 2 and 2 and a frame 3; and a printedwiring board 4 accommodated in this casing. Outer dimensions of thecasing are length ×width=36.4 mm×42.8 mm and height=3.3 mm.

FIG. 3 is a perspective view of the two panel plates 2 and 2. Thesepanel plates 2 and 2 are composed of thin plates made of stainless steel(SUS 304) and each having the same shape. An embossing treatment isperformed to the surface side of each panel plate 2, and so fingerprintsor the like are not easily attached thereto. Also, a plurality ofclaw-like engaging parts 5 are provided on the periphery of each panelplate 2.

Respective engaging parts 5 are integrally formed on each panel plate 2.Although not particularly limited, five engaging parts 5 are provided ineach of both sides thereof and one engaging part 5 is provided in eachof both ends of the connector 9 side and six engaging parts 5 areprovided in a side opposite thereto. Thus, a total of eighteen engagingparts 5 are provided. Each of the engaging parts 5 has tensile strengthenough to bear a load of 1 Kgf or more.

As shown in the enlarged view of FIG. 4, there are two types of engagingparts 5, that is, one having a lance 6 and the other having a hole 7.The engaging parts 5 each having the lance 6 and the engaging parts 5each having the hole 7 are alternately arranged along the peripheries ofthe respective panel plates 2 and 2. As described later, in the assemblyof the CF card 1, each lance 6 of the engaging parts 5 on one panelplate 2 is inserted into each hole 7 of the engaging parts 5 on theother panel plate 2.

FIG. 5 is a perspective view of the frame 3, and FIG. 6 is a plan viewof the same. The frame 3 has an outline formed in an approximateU-shape, and is constituted by integrally molding a resin having goodmoldability, for example, PBT (Polybutylene telephthalate) containing15% of glass fiber, or the like. Also, an embossing treatment isperformed to the outer surface of the frame 3, such that fingerprints orthe like are not easily attached thereto and sinks caused due to theinjection molding thereof are made inconspicuous.

A long groove 8 to which the periphery of each panel plate 2 is fittedis provided in each of the upper and lower surfaces of the frame 3.Further, through holes 10 into which the engaging parts 5 of each panelplate 2 are inserted are provided in the long groove 8.

FIG. 7 is a perspective view of the printed wiring board 4. The printedwiring board 4 is constituted by forming Cu wirings (not shown) on thesurface of, for example, a plate made of epoxy resin containing glassfiber (glass epoxy), and packages 11 are mounted on the main surfacethereof. In each package 11, a semiconductor chip (not shown) in which aflash memory for data storage is formed is sealed. Further, theconnector 9 for connecting the CF card 1 to various electronicequipments such as a digital camera, a handheld PC, an audio recorderand the like is attached to one side of the printed wiring board 4. Inthe case of the CF card type I, the interface of the connector 9 hasfifty pins.

As described above, in the CF card 1 according to this embodiment, thecasing for accommodating the printed wiring board 4 is constituted by anextremely small number of components, that is, two panel plates 2 and 2each having the same shape and one frame 3.

Next, an assembly method of the CF card 1 constituted in theabove-described manner will be described with reference to FIGS. 8 to20.

FIG. 8 is a perspective view showing a part of a hoop material 20 havinga multiple series of panel plates 2. Each of the panel plates 2 issupported by carriers 21 via notches 22 provided at the four cornersthereof. In the drawings, almost three panel plates 2 are illustrated.However, since the hoop material 20 has actually a multiple series ofabout one thousand panel plates 2, it is wound on a reel or the like andis stored in this state.

The CF card 1 is assembled, for example, by: inserting the engagingparts 5 of each panel plate 2, into the through holes 10 (see FIG. 6)formed in the long groove 8 provided in the frame 3 as shown in FIG. 9;then mounting the printed wiring board 4 on the panel plate 2 located atthe inside of each frame 3 as shown in FIG. 10; and thereafter insertingthe engaging parts 5 of the panel plate 2 located in a second hoopmaterial 20, into the through holes 10 formed in the long groove 8 fromthe surface of a opposite side of the frame 3 as shown in FIG. 11.

As shown in FIG. 12, attachment of the panel plate 2 to the frame 3 canalso be made after the plate 2 is separated from the hoop material 20.As a jig for attaching the panel plate 2 to the frame 3, for example, asshown in FIG. 13, the jig can also be used which has a receiving table32 provided with four walls 31 and restricting the position of the frame3, and a punch 33 having an area almost equal to that of the panel plate2.

In this case, the frame 3 is firstly positioned at each inside of thewalls 31 of the receiving table 32, and thereafter the engaging parts 5of the separated panel plate 2 are pressed into the through holes 10 ofthe frame 3 by using the punch 33. At this time, since the pressed loadis 1 Kg or less per engaging part 5, each engaging part 5 can be easilypressed thereinto.

Next, as shown in FIG. 14, the printed wiring board 4 is mounted on thepanel plate 2 attached to the frame 3. Thereafter, the four notches 22connecting the panel plate 2 and the carrier 21 are cut out as shown inFIG. 15. In this case, for example, by providing a halfcut 23 in a partof each notch 22 in advance as shown in FIG. 16 and by pushing eachnotch 22 with using a eyeleteer 24 or the like to drop the notch intothe long groove 8 of the frame 3 as shown in FIGS. 17A and 17B, thenotches 22 can be easily cut out.

Next, as shown in FIG. 18, the other panel plate 2 is attached to thesurface of an opposite side of the frame 3 with using the jig shown inFIG. 13, or the like.

FIG. 19A is a cross-sectional view showing a engaging state of the twopanel plates 2 and 2 attached to the frame 3, and FIG. 19B is a frontview showing the same.

The panel plates 2 and 2 are attached by using the above-describedpushing jig, that is, by: pressing the engaging parts 5 and 5 of thepanel plates 2 and 2 into the through holes 10 of the frame 3 from aboveand below; and inserting the lances 6 of the engaging parts 5 of onepanel plate 2 into the corresponding holes 7 of the engaging parts 5 ofthe other panel plate 2.

As shown in the drawings, the engaging parts 5 are bent so that eachlance 6 thereof can be located at an inner position and each hole 7thereof can be located at an outer position. Therefore, there occur nogaps between the engaging parts 5 and the inner walls of the throughholes 10. Thus, the lances 6 is easily inserted into the holes 7 bysimply pressing the engaging parts 5 and 5 of the panel plates 2 and 2into the through holes 10, and once the lances 6 are inserted into theholes 7, the panel plates 2 and 2 are not detached from each other evenif pulled from the outside.

Also, in each of the panel plates 2 and 2, the engaging parts 5 eachhaving the lance 6 and the engaging parts 5 each having the holes 7 arealternately arranged, and the number of the lances 6 and that of theholes 7 are equal to each other in the respective panel plates 2 and 2.Therefore, it is possible to evenly press the engaging parts 5 and 5 ofthe panel plates 2 and 2 thereinto.

As described above, the CF card 1 according to this embodiment hascharacteristics of the fact that the panel plates having once beenassembled are extremely difficult to disassemble because the panelplates 2 and 2 have a rigidly engaging structure, and that high securityis obtained because the engaging parts 5 are significantly deformed whenthe panel plates 2 are forcibly and strongly pulled from the outside andbecause traces caused by the pull are inevitably left.

Also, the CF card 1 according to this embodiment has characteristics ofthe fact that since the rigidly engaging structure is obtained by simplypressing the engaging parts 5 and 5 of the two panel plates 2 and 2 intothe through holes 10 of the frame 3 with using the simple pushing jig,special apparatus such as an ultrasonic welding machine or the like isnot required and it is possible to reduce the cost of the equipmentinvestment for the assembly.

As shown in FIG. 20, after the first panel plate 2 is inserted into theframe 3, the second panel plate 2 can also be inserted thereinto beforeeach panel plate 2 is separated from the hoop material 20.

In this case, the frame 3 in which the first panel plate 2 has beeninserted is first carried to a right-hand stage, and then the secondpanel plate 2 is inserted into the frame in which the first panel plate2 has been inserted. Thereafter, the frame 3 is lifted by the carrier 21and carried to a left-hand stage, and then the second panel plate 2 isseparated from the carrier 21 by cutting the notches 22. It is alsopossible that the hoop material 20 together with the frame 3 is wound ona reel after the insertion of the second panel plate 2 into the frame 3at the right-hand stage, and then is delivered to a maker, and, at thetime, the second panel plate 2 is separated from the carrier 21.

Thus, the automation of the assembly can be easily attained in variousmanners by forming a multiply series of the panel plates 2. Therefore,the reduction in the assembly cost and in the lead time can be achieved.

In the foregoing, the inventions made by the inventors thereof have beendescribed in detail based on the embodiments. However, needless to say,the present invention is not limited to the above-mentioned embodiments,and can be variously changed and modified without departing from thegist thereof.

In the foregoing embodiments, the case where the present invention isapplied to the CF card type-I has been described. However, needless tosay, the present invention can be applied to the CF card type-II havinga casing with a thickness of 5 mm. Further, the engagement structure ofthe panel plates according to the present invention can be applied notonly to the CF card in which the interface of the connector hassixty-eight pins but also to various memory cards such as a PC card orthe like.

INDUSTRIAL APPLICABILITY

The semiconductor device according to the present invention isconstituted by a small number of components and so can be assembledsimply. Therefore, by applying to the memory card connected to variouselectronic equipments such as a digital camera, a handheld PC, an audiorecorder and the like, the manufacturing cost thereof can be reduced.

What is claimed is:
 1. A semiconductor device comprising: a casingconstituted by a frame having first and second surfaces and a pluralityof through holes penetrating through both of said first and secondsurfaces, a first panel plate attached to said first surface of saidframe, and a second panel plate attached to said second surface of saidframe, a printed wiring board on which a semiconductor chip is mountedbeing accommodated in said casing, wherein a plurality of engaging partseach having a lance or a hole arranged to engage a lance are formed onthe peripheries of said first and second panel plates, respectively,said lance being a protruding portion extending toward an outer sidedirection of said casing, said engaging parts formed on said first panelplate and said engaging parts formed on said second panel plate areinserted into said plurality of through holes formed in said frame, suchthat said lances are inserted into corresponding ones of said holes, andsaid first panel plate and said second panel plate each have a similarshape, and the engaging parts each having said lances and the engagingparts each having said holes are alternately arranged in said first andsecond plates.
 2. The semiconductor device according to claim 1, whereinsaid lance is bent so as to be located at an inner position of saidframe and said hole is bent so as to be located at an outer position ofsaid frame.
 3. The semiconductor device according to claim 1, whereinsaid engaging parts are integrally formed with said panel plates.
 4. Thesemiconductor device according to claim 1, wherein said frame is formedby integrally molding a resin.
 5. The semiconductor device according toclaim 1, wherein an embossing treatment is performed to each outersurface of said first and second panel plates.
 6. The semiconductordevice according to claim 1, wherein an embossing treatment is performedto an outer surface of said frame.
 7. The semiconductor device accordingto claim 1, wherein a semiconductor chip in which a flash memory isformed is mounted on said printed wiring board.